inputs to be present, and OR requires one input to be present to provide output. NOT reverses the input; if there is no pulse on the input line, the source goes directly to the output, but if there is a pulse on the input line, switch one is closed, and the current moves to switch two. These logic gates make up circuits which make up logical devices, such as the central processing unit. (I, II).
             Brain, Marshall. "How Hard Disks Work." Online. Internet. Available HTTP://www.howstuffworks.com/
             A hard disk is a device used to store programs and data for later use. A typical hard disk holds eight to eleven gigabytes, which is stored in the form of files. Inside the hard disk is a platter which spins 3,600 to 7,200 RPMs. All the information that needs to be recalled is recorded on this platter. The information is divided in sectors, and sectors are grouped into tracts. Hard disks are used in nearly every desktop computer and server in use today; you can even find them in some VCR and camcorder devices instead of tapes. (III).
             Dunphy, Chris. "RAM-O-Rama: Your Field Guide to Memory Types." Maximum PC Mar. 2000: 67.
             "Extra memory never hurt." Inside every computer is the "fastest memory of all," the processor's registers. A typical central processing unit has a few dozen registers, and each one is able to store a single value which is directly wired into the CPU. Whenever the CPU needs to "crunch" a number that is not already in a register, a memory request is generated, and the CPU's internal memory controller goes to work. All modern CPUs try to crunch a constant stream of instructions by throwing some Level 1 cache into the mix. Typical word processing and web "surfing" can be handled with ease by this memory. (III).
             Frederick, Franz J. Guide to Microcomputers. Washington, D.C.: Association for Educational Communications and Techn...